Added the `geocodeAfterResult` option

The `geocodeAfterResult` basically supplements the `blur` option. 

Trigger geocode on blur event only if user has not explicitly selected a result from the dropdown. Keep in mind that the assumption is that after user selected a result but changed the input afterwards, the location will be geocoded nonetheless.

To reproduce the problem open the blur.html and set the `geocodeAfterResult` option to false.
* Type City of London, United Kingdom
* Select location and press TAB.
* Geocode is triggered because of the blur option and the input is converted to 'London, UK'.
As you can see it is impossible to have the blur option enabled and keep 'City of London' as a city.

Now set the `geocodeAfterResult` to true.
* Type City of London, United Kingdom
* Select the first result and press TAB. Location 'City of London' is preserved. If user does not select a result, it will geocode as should.